st: gpscore for propensity score of 4 observed groups

[oconnor7@u.washington.edu]

Hi,

I have technical question regarding gpscore.

If my treatment variable is type of injury severity, what should I put for "cutpoints", "index", and "nq_gps"? The treatment level has four different levels of injury severity.

What I am seeking is to create a propensity score for the likelihood that a person develops a certain type of injury, in this case TBI, based upon a list of covariates.

This is the syntax I used for a preliminary analysis:

gpscore  age child_gender prev_anxiety prev_depn prev_adhd prev_behavioral prev_other_mh, t(inj_severity) gpscore(mygps) predict(hat_inj_sev) sigma(hat_sd) cutpoints (inj_severity) index(p50) nq_gps(4)

Again, I am unsure of cutpoints, index, and nq_qps given that I have four established groups for the treatment variable.


Thank you, 
Stephen



Stephen O'Connor
Senior Fellow
Harborview Injury Prevention & Research Center
Department of Psychiatry & Behavioral Sciences
University of Washington at Harborview Medical Center



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